Wheat as model to study avocado root rot and interactions with rhizobacteria

Abstract

Avocado white root rot (AWRR), caused by Rosellinia necatrix, presents significant research challenges due to the practical difficulties and limited availability of using avocado plants as experimental model. To address these limitations, a novel wheat-based model has been developed. This model facilitates the study of rhizospheric interactions between R. necatrix and beneficial bacteria isolated from avocado roots. Wheat seeds were challenged in pots with R. necatrix, which effectively colonizes and infects wheat roots, inducing observable aerial symptoms that enable quantitative assessment of disease severity. Additionally, beneficial bacteria, originally isolated from avocado roots, demonstrate comparable colonization efficiency on wheat roots. The use of fluorescent-tagged microbial strains allowed visualization of the interactions taking place at the wheat root. This wheat model proved effective for evaluating biocontrol agents, yielding consistent results with previous observations in avocado plants. These findings indicate that wheat can be considered an additional tool for investigating AWRR-related rhizospheric dynamics.